Process for the production of resinlike condensation products.



rm'raronnax, or BERLIN, GERMANY.

' rnoonssv FOR THE rnonoc'rron orzmsmtixn CONDENSATION rnonnc'rs. I

No Drawing.

To all whom it may concern:

Be it known that I, Dr. Fnrrz PoLLAK, analytical chemist, residing inBerlin, Ger- .many, (whose post-oilice address is 107Kiiniggratzerstrasse, Berlin, Germany,) have invented certain new anduseful Improvements in Processes for the Production I of ResinlikeCondensation Products; and I do herdby declare the following to be afull, clear, and exact description of the invention,

such as w1ll enable others skilled in the art to which it appertains tomake and use the same. l F

It is known that-phenols can be condensed to form soluble resins withformaldehyde and its polymers in the presence of contact however,

media. These methods present the defect, that the condensation productsob tained obstinately retain the contact medium employed, even afterrepeated cleaning. This property renders it necessary to have recourseto a series of washing, cleansing,

and purifying operations which render the 5 If, on the otherconsiderably more difiicult. hand, the usual formaldehyde solution isallowed toact upon crystallized phenols without a contact agent, it isonly after heating for several days that any reaction takes place andeven after lengthy boiling this always remains incomplete, sothat theresin obtained is rendered impure by large quantities of unmodifiedprimary material. Now it has been found that it is possible to operatequickly and readily without employing contact media if instead of a)formaldehyde solution. the anhydrous polymerids of formaldehyde soldunder the name of trioxymethylene and representing a mixture of {5 andpoly-oxymethylene are employed and caused to act in a fine pulverulentform upon phenols, Even at a temperature of 80 (1., so vigorous a retechnical process action takes place with selfheating of the "4 v drousdiluents.

mass that it is necessary sometimes to moderate this reaction by theaddition of anhy- This action of anhydrous trioxymethylene'is not onewhich could have have been far more on the contrary it would likely forthe polymerized-formaldehyde to behave less aggresbeen foreseen.

sively than the usual formaldehyde solunets to react more tion, as it isusual for monomolecular prodmolecular bodies. T e polymerized dratespresent in highly concentrated formald hyde do not present the propertyof re- Speciflcation of Iletters Patent.

vi orously than multi; hy-' Patented Jan, 2, 1917.

Application filed June 4, 1912. Serial No. 701,572.

' acting exothermically with phenols. In the case of the anhydroustrioxymethylene this property s not attributable to the higherconcentration of the mass, asthe reaction itself takes placevigorouslyand with self heating even 1n case that somuch water is addedto the massas is necessary for the formation of a trioxymethylene trihydrate.

The novel process presents the further advantage of permitting of anexact measurement of the formaldehyde employed such as has not hithertobeen-possible. For example in operating in the usual manner with a 40%aqueous formaldehyde solution with the addition of a contact medium, thereaction never takes place otherwise than incompletely, because theresin formed does not remain in solution to the end. As soon as theconcentration of the formaldehyde solution has been suitably lowered,the resin is precipitated and carries with it the free phenol stillpresent. By this means any further reaction. .of the latter with theformaldehyde is,prevented and further heatmg of the mass thenon'lyproduces the result that the formaldehyde solution is converted i intopara formaldehyde by the action of the contact medium and is therebyprecipitated; The resin therefore contains'both free phenol and freepara formaldehyde in suspension. 1 If 1t is dehydrated, the phenolescapes at high temperatures and leaves behind brownempyreumatic'substances which render the resin impure and color it. The melting pointof the resin is also relatively lower, which is a disadvantage initspractical employment in place of shellac.

, The finely powdered anhydrous trioxy methylene: dissolves in .onlywhen this solution has taken. place does the mass become self heated sothat'water the hot phenol and is formed. Upon dehydration the resinformed yields but small quantities of volatile substances. Thedehydrated resin is on] slightly colored yellow. It only softens in=oiling water; The resin is soluble in alcohol, ether, acetone and sodalye without residue and can be used in the usual way.

The novel process can practice in the following manner:

Example I: 94: parts of crystallized phenol.

and 25.7 parts of finely powdered anhydrous trioxymethlene are mixedwith 3 arts of water and heated at 85fin the re ux condenser whileagitating preferably'in a current of inert gas. With vigorous boiling becarried into or its polymers.

the temperature of the substance rises approximately 113. As soon as theinternal heating ceases, the substance is still heated for a short timeto 100 to 110 and then tapped off into the dehydration vessel. It

is there heated to 160 to 170 whena scum forms and the substance becomesclear. It is then ready for use. Equimolecular quantities of the cresolsor other homologous phenols can be employed instead of the phenol. Theresins formed can of course be treated to form insoluble resins eitherbefore or after their dehydration by the addition of further quantitiesof formaldehyde But the insoluble resins which may thus be obtained,still present some deficiencies which may render them unsuitable forpractical use. When exposed to the air forsome time, they are apt tochange their color; during the indurating process the surface layerusually assumes a red tint. Their transparency is in many casesdeficient and very often an opaque product is obtained, In orderto-avoid all this, it becomes necessary to submit the solubleintermediate products described above to a special treatment during andafter the initial condensation process.

It is known that a soluble transparent resin can easily be obtained byheating phenols with formaldehyde solution for some days. However, ifanhydrous trioxy methylene is used instead of formaldehyde, owing to theabsence of water the condensation-which takes place differs in somerespects from the condensation obtained with formaldehyde. The productsobtained probably possess a higher degree of polymerizatlon; they arevery sensible to the influence of water which when hot is chemicallybound by them. Therefore, if it is in-.

tended to make a soluble transparent intermediate product for use in themanufacture oftransparent insoluble resins,'it is advisable to soconduct the initial condensation process, that the water formed duringthe reaction be distilled off through a condenser,

" the distillate be collected and the formaldehyde contained therein, beregenerated.

.Care should be taken. not to add the whole of the trioxy methylenetothe phenol in one portionrfor, if this would be done, a

sudden development of steam would ensue and large quantities offormaldehyde would be carried off with the steam and get lost. I havefound that the quantity of formaldehyde carried away depends on thevelocity of steam generation, and thisagain will difl'er within widelimits according to the surface presented by the liquid. It istherefore. preferable to gradually add small quan tities of anhydroustrioxy methylene, so that the generation of steam takes place slowly andregularly. t If the process be conducted after this fashion, the loss offormaldehyde may be kept very small. There is however. one drawback tothe gradual adding of anhydrous trioxy methylene as'described. Smallquantities of anhyadd to it a small quantity of orthoor metacresol, orelse to replace the crystallized phenol 'by one of minor purity whichcontains per 86 some ortho-cresol.

I have further found that in the soluble percents. of cresol, chieflyresins obtained by this method part of the phenol is bound very firmly,while another part is bound less firmly; this part of the phenolprobably forms substituted ethers of benzyl alcohol. These ethers mayeasily be decomposed, the phenol being split off. It is possible toeffect this decomposition. by treating the mass with cold water, waterat .a temperature less than 40 0., andithis reaction may be made use ofwith advantage in the purification of the mass, as the heterogeneoussubstances (impurities) form an emulsion with water and can thus be re'moved together with the phenol. The soluv ble resin, which results fromthis purification, is a white soap like mass, which, when warmed up,sets free'part of the suspended water. The rest of the water cannot beremoved unless the product be heated above C. The product resulting fromsuch heating of the mass above 105 C. is a light colored transparenttough soluble resin which is now ready foruse in the proclyction ofinsoluble resins of the highest q ality. 'I proceed for instance asfollows:

Example II: A. mixture of 37 0 parts of pure crystallized carbolic acidand 6 parts of meta-cresol is heated in a water or oil bath under goodstirring. A neutral gas such as for instance nitrogen may beintroducedinto this mixture, to which is then added 20 parts of finelypowdered anhydrous trioxy methylene. The temperature of the bath is thenallowed to rise up to 85 degr. C., when an energetic reaction will setin, the temperature of the mixture rising above 100 degr. C. When thetemperature has dropped again below 100 degr. 0., I add another 20 partsof anhydrous trioxy methylene, and this operation is repeated until inall 80 parts of anhydrous trioxy methylene have been added, During theexothermic reaction a small quantity of water distils over, carryingwith it some phenol and traces of formaldehyde. This mass is nowfiltered, allowed to cool down and then repeatedly washed with largequantities of water of less than 40 degr. C. The remaining product isgraduall heated above 105 C; preferably up to a out 130 degr. C. wherebythe water and most of the free phenol are distilled over. It is notadvisable to heat the mass above 130 degr. C., as then the mass willassume a brownish co1or. The product obtained after cooling is aslightly yellowish resin, soluble in alco hol, ether, acetone andcaustic soda and smelling but very faintly after phenol.

The manner of carrying out this process as well as the quantity ofanhydrous trioxy methylene employed may be varied within wide limits.With more anhydrous trioxy methylene a thicker product will be obtained.If an excessive quantity of anhydrous trioxy methylene had been admixed,the product obtained can not be washed out roperly with cold water andwill have to e heated in order to entirely remove the henol; thistreatment however will result 1n the production of a reddish or brownishproduct. If on ,the contrary the quantity of anhydrous trioxy methyleneused is too small, the loss ofiphenol will be far greater.

It is therefore advisable to use about the quantities indicated in theexample given above, which correspond to 3 molecules of phenol and 2molecules of anhydrous trioxy methylene.

Having now particularly described and ascertained'the nature of my saidinvention and in whatmanner the same is to be performed, I declare thatwhat I claim is:

1. The method of producing soluble sheltrioxy methylene, the step ofgradually adding the anhydrous trloxy methylene in several portions.

4. In a method of producing soluble shellac-like resins by heating amixture of a body of the phenolic series and an anhydrous trioxymethylene, the step of washing the reaction-product with Water of lessthan 40 degr. C.

5. The method of producing soluble shellac-like resins which consists inheating a mixture of a crystallized body of the phenolic series and ananhydrous trioxy methyl:

ene, washing the reaction product with water of less than 40 degr. C.and heating the remaining mass ab0ve105 degr. C.

1 6. The method of producing soluble shellac-like resins which consistsin heating a mixture of a crystallized body of the phenolic series andan anhydrous trioxy methylene in the molecular proportion of about 3: 2,filtering, cooling, repeatedly washing the reaction product, with waterof less than 40 degr. G. and heating it above 105 degr. C. In testimonwhereof I aflix my signature, in presence 0 two witnesses.

I Da. FRITZ-POLLAK. Witnesses:

HENRY HAsrnR, WOLDEMAR HAUPT.

It. is hereby certified that in Inttara Patent No. 1,210 982, grantedJanuary 2, 1917, upon the application of Fritz Pollak, of Berlin,Germany, for an improvement in "Prooessas for the Production ofResinlike Condensation Products," an error anneal-s in the printedspecification requiring correctiofi as follows: Page 1, lines 45-46,strike out. the word "anhydrous"; and that the said Lott/am Patantshould be read with this correction thareifi that tho some may conformto the record of tho case in tho Patent. Office.

Signed and sea ed this 13th day of February, A. D., 1917.

R. F. WHITEHEAD,

Acting Cbmmiuim of Patent

